Abstract

We demonstrate a new method to improve the performance of photonic assisted analog to digital converters (ADCs) that are based on frequency down-conversion obtained by optical under-sampling. The under-sampling is performed by multiplying the radio frequency signal by ultra-low jitter broadband phase-locked optical comb. The comb wave intensity has a smooth periodic function in the time domain rather than a train of short pulses that is currently used in most photonic assisted ADCs. Hence, the signal energy at the photo-detector output can be increased and the signal to noise ratio of the system might be improved without decreasing its bandwidth. We have experimentally demonstrated a system for electro-optical under-sampling with a 6-dB bandwidth of 38.5 GHz and a spur free dynamic range of 99 dB/Hz2/3 for a signal with a carrier frequency of 35.8 GHz, compared with 94 dB/Hz2/3 for a signal at 6.2 GHz that was obtained in the same system when a pulsed optical source was used. The optical comb was generated by mixing signals from two dielectric resonator oscillators in a Mach-Zehnder modulator. The comb spacing is equal to 4 GHz and its bandwidth was greater than 48 GHz. The temporal jitter of the comb measured by integrating the phase noise in a frequency region of 10 kHz to 10 MHz around comb frequencies of 16 and 20 GHz was only about 15 and 11 fs, respectively.

© 2014 Optical Society of America

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References

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    [Crossref] [PubMed]
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    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref]

2012 (5)

2011 (1)

2010 (2)

2009 (2)

A. Feldster, Y. P. Shapira, M. Horowitz, and A. Rosenthal, “Optical under-sampling and reconstruction of several bandwidth-limited signals,” J. Lightwave Technol. 27, 1027–1033 (2009).
[Crossref]

H. Byun, A. Hanjani, S. Frolov, E. P. Ippen, D. Pudo, J. Shmulovich, and F. X. Kartner, “Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser,” IEEE Photon. Technol. Lett. 21, 763–765 (2009).
[Crossref]

2008 (1)

2007 (1)

2006 (1)

K. G. Wilcox, H. D. Foreman, J. S. Roberts, and A. C. Tropper, “Timing jitter of 897 MHz optical pulse train from actively stabilised passively modelocked surface-emitting semiconductor laser,” Electron. Lett. 42, 159–160 (2006).
[Crossref]

2005 (1)

A. Zeitouny, Z. Tamir, A. Feldster, and M. Horowitz, “Optical sampling of narrowband microwave signals using pulses generated by electroabsorption modulators,” Opt. Commun. 256, 248–255 (2005).
[Crossref]

2004 (1)

M. E. Grein, H. A. Haus, Y. Chen, and E. P. Ippen, “Quantum-limited timing jitter in actively modelocked lasers,” IEEE J. Quantum. Elect. 40, 1458–1470 (2004).
[Crossref]

2003 (1)

1999 (3)

P. L. Liu, K. J. Williams, M. Y. Frankel, and R. D. Esman, “Saturation characteristics of fast photodetectors,” IEEE Trans. Microw. Theory Techn. 47, 1297–1303 (1999).
[Crossref]

R. H. Walden, “Analog-to-digital converter survey and analysis,” IEEE J. Sel. Areas Commun. 17, 539–550 (1999).
[Crossref]

T. R. Clark, T. F. Carruthers, P. J. Matthews, and I. N. Duling, “Phase noise measurements of ultrastable 10 GHz harmonically modelocked fibre laser,” Electron. Lett. 35, 720–721 (1999).
[Crossref]

1998 (1)

A. Yariv and R. G. M. P. Koumans, “Time interleaved optical sampling for ultra-high speed A/D conversion,” Electron. Lett. 34, 2012–2013 (1998).
[Crossref]

1997 (1)

R. Helkey, J. C. Twichell, and C. Cox, “A down-conversion optical link with RF gain,” J. Lightwave Technol. 15, 956–961 (1997).
[Crossref]

Benedick, A.

Benedick, A. J.

A. J. Benedick, J. G. Fujimoto, and F. X. Kärtner, “Ultrashort laser pulses: optical flywheels with attosecond jitter,” Nature Photon. 6, 97–100 (2012).
[Crossref]

Byun, H.

Carruthers, T. F.

T. R. Clark, T. F. Carruthers, P. J. Matthews, and I. N. Duling, “Phase noise measurements of ultrastable 10 GHz harmonically modelocked fibre laser,” Electron. Lett. 35, 720–721 (1999).
[Crossref]

Chen, J.

Chen, Y.

M. E. Grein, H. A. Haus, Y. Chen, and E. P. Ippen, “Quantum-limited timing jitter in actively modelocked lasers,” IEEE J. Quantum. Elect. 40, 1458–1470 (2004).
[Crossref]

Clark, T. R.

T. R. Clark, T. F. Carruthers, P. J. Matthews, and I. N. Duling, “Phase noise measurements of ultrastable 10 GHz harmonically modelocked fibre laser,” Electron. Lett. 35, 720–721 (1999).
[Crossref]

Cox, C.

R. Helkey, J. C. Twichell, and C. Cox, “A down-conversion optical link with RF gain,” J. Lightwave Technol. 15, 956–961 (1997).
[Crossref]

Dahlem, M. S.

Demirbas, U.

DiLello, N. A.

Duling, I. N.

T. R. Clark, T. F. Carruthers, P. J. Matthews, and I. N. Duling, “Phase noise measurements of ultrastable 10 GHz harmonically modelocked fibre laser,” Electron. Lett. 35, 720–721 (1999).
[Crossref]

Esman, R. D.

P. L. Liu, K. J. Williams, M. Y. Frankel, and R. D. Esman, “Saturation characteristics of fast photodetectors,” IEEE Trans. Microw. Theory Techn. 47, 1297–1303 (1999).
[Crossref]

Feldster, A.

A. Feldster, Y. P. Shapira, M. Horowitz, and A. Rosenthal, “Optical under-sampling and reconstruction of several bandwidth-limited signals,” J. Lightwave Technol. 27, 1027–1033 (2009).
[Crossref]

A. Zeitouny, Z. Tamir, A. Feldster, and M. Horowitz, “Optical sampling of narrowband microwave signals using pulses generated by electroabsorption modulators,” Opt. Commun. 256, 248–255 (2005).
[Crossref]

Feldtser, A.

Fleyer, M.

Foreman, H. D.

K. G. Wilcox, H. D. Foreman, J. S. Roberts, and A. C. Tropper, “Timing jitter of 897 MHz optical pulse train from actively stabilised passively modelocked surface-emitting semiconductor laser,” Electron. Lett. 42, 159–160 (2006).
[Crossref]

Frankel, M. Y.

P. L. Liu, K. J. Williams, M. Y. Frankel, and R. D. Esman, “Saturation characteristics of fast photodetectors,” IEEE Trans. Microw. Theory Techn. 47, 1297–1303 (1999).
[Crossref]

Frolov, S.

H. Byun, A. Hanjani, S. Frolov, E. P. Ippen, D. Pudo, J. Shmulovich, and F. X. Kartner, “Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser,” IEEE Photon. Technol. Lett. 21, 763–765 (2009).
[Crossref]

Fujimoto, J. G.

Geis, M. W.

Grein, M. E.

Hanjani, A.

H. Byun, A. Hanjani, S. Frolov, E. P. Ippen, D. Pudo, J. Shmulovich, and F. X. Kartner, “Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser,” IEEE Photon. Technol. Lett. 21, 763–765 (2009).
[Crossref]

Hargreaves, J. J.

Haus, H. A.

M. E. Grein, H. A. Haus, Y. Chen, and E. P. Ippen, “Quantum-limited timing jitter in actively modelocked lasers,” IEEE J. Quantum. Elect. 40, 1458–1470 (2004).
[Crossref]

Helkey, R.

R. Helkey, J. C. Twichell, and C. Cox, “A down-conversion optical link with RF gain,” J. Lightwave Technol. 15, 956–961 (1997).
[Crossref]

Holzwarth, C. W.

Horowitz, M.

Hoyt, J. L.

Ippen, E. P.

Jung, K.

Juodawlkis, P. W.

Kanter, G. S.

J. Liu, G. S. Kanter, S. X. Wang, and P. Kumar, “10 GHz ultra-stable short optical pulse generation via phase-modulation enhanced dual-loop optoelectronic oscillator,” Opt. Commun. 285, 1035–1038 (2012).
[Crossref]

Kartner, F. X.

H. Byun, A. Hanjani, S. Frolov, E. P. Ippen, D. Pudo, J. Shmulovich, and F. X. Kartner, “Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser,” IEEE Photon. Technol. Lett. 21, 763–765 (2009).
[Crossref]

Kärtner, F. X.

Khilo, A.

Kim, C.

Kim, H.

Kim, J.

Kim, T. K.

Kolodziejski, L. A.

Koumans, R. G. M. P.

A. Yariv and R. G. M. P. Koumans, “Time interleaved optical sampling for ultra-high speed A/D conversion,” Electron. Lett. 34, 2012–2013 (1998).
[Crossref]

Kumar, P.

J. Liu, G. S. Kanter, S. X. Wang, and P. Kumar, “10 GHz ultra-stable short optical pulse generation via phase-modulation enhanced dual-loop optoelectronic oscillator,” Opt. Commun. 285, 1035–1038 (2012).
[Crossref]

Li, D.

Liu, J.

J. Liu, G. S. Kanter, S. X. Wang, and P. Kumar, “10 GHz ultra-stable short optical pulse generation via phase-modulation enhanced dual-loop optoelectronic oscillator,” Opt. Commun. 285, 1035–1038 (2012).
[Crossref]

Liu, P. L.

P. L. Liu, K. J. Williams, M. Y. Frankel, and R. D. Esman, “Saturation characteristics of fast photodetectors,” IEEE Trans. Microw. Theory Techn. 47, 1297–1303 (1999).
[Crossref]

Lyszczarz, T. M.

Matthews, P. J.

T. R. Clark, T. F. Carruthers, P. J. Matthews, and I. N. Duling, “Phase noise measurements of ultrastable 10 GHz harmonically modelocked fibre laser,” Electron. Lett. 35, 720–721 (1999).
[Crossref]

Motamedi, A.

Nam, C. H.

Nejadmalayeri, A. H.

Orcutt, J. S.

Park, M. J.

Peng, M. Y.

Perrott, M.

Perrott, M. H.

Petrich, G. S.

Pile, B. C.

Popovic, M. A.

Pudo, D.

H. Byun, A. Hanjani, S. Frolov, E. P. Ippen, D. Pudo, J. Shmulovich, and F. X. Kartner, “Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser,” IEEE Photon. Technol. Lett. 21, 763–765 (2009).
[Crossref]

Ram, R. J.

Roberts, J. S.

K. G. Wilcox, H. D. Foreman, J. S. Roberts, and A. C. Tropper, “Timing jitter of 897 MHz optical pulse train from actively stabilised passively modelocked surface-emitting semiconductor laser,” Electron. Lett. 42, 159–160 (2006).
[Crossref]

Rosenthal, A.

Rubiola, E.

E. Rubiola, Phase Noise and Frequency Stability in Oscillators (Cambridge University Press, New York, 2009), Chap. 1.

Sander, M. Y.

Sennaroglu, A.

Shapira, Y. P.

Shen, H.

Shmulovich, J.

H. Byun, A. Hanjani, S. Frolov, E. P. Ippen, D. Pudo, J. Shmulovich, and F. X. Kartner, “Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser,” IEEE Photon. Technol. Lett. 21, 763–765 (2009).
[Crossref]

Smith, H. I.

Smulakovsky, V.

Song, Y.

Sorace-Agaskar, C. M.

Spector, S. J.

Sun, J.

Tamir, Z.

A. Zeitouny, Z. Tamir, A. Feldster, and M. Horowitz, “Optical sampling of narrowband microwave signals using pulses generated by electroabsorption modulators,” Opt. Commun. 256, 248–255 (2005).
[Crossref]

Taylor, G. W.

Titi, G. W.

Tropper, A. C.

K. G. Wilcox, H. D. Foreman, J. S. Roberts, and A. C. Tropper, “Timing jitter of 897 MHz optical pulse train from actively stabilised passively modelocked surface-emitting semiconductor laser,” Electron. Lett. 42, 159–160 (2006).
[Crossref]

Twichell, J. C.

Valley, G. C.

Walden, R. H.

R. H. Walden, “Analog-to-digital converter survey and analysis,” IEEE J. Sel. Areas Commun. 17, 539–550 (1999).
[Crossref]

Wang, J. P.

Wang, S. X.

J. Liu, G. S. Kanter, S. X. Wang, and P. Kumar, “10 GHz ultra-stable short optical pulse generation via phase-modulation enhanced dual-loop optoelectronic oscillator,” Opt. Commun. 285, 1035–1038 (2012).
[Crossref]

Wilcox, K. G.

K. G. Wilcox, H. D. Foreman, J. S. Roberts, and A. C. Tropper, “Timing jitter of 897 MHz optical pulse train from actively stabilised passively modelocked surface-emitting semiconductor laser,” Electron. Lett. 42, 159–160 (2006).
[Crossref]

Williams, K. J.

P. L. Liu, K. J. Williams, M. Y. Frankel, and R. D. Esman, “Saturation characteristics of fast photodetectors,” IEEE Trans. Microw. Theory Techn. 47, 1297–1303 (1999).
[Crossref]

Yariv, A.

A. Yariv and R. G. M. P. Koumans, “Time interleaved optical sampling for ultra-high speed A/D conversion,” Electron. Lett. 34, 2012–2013 (1998).
[Crossref]

Yoon, J. U.

Younger, R. D.

Zeitouny, A.

A. Zeitouny, Z. Tamir, A. Feldster, and M. Horowitz, “Optical sampling of narrowband microwave signals using pulses generated by electroabsorption modulators,” Opt. Commun. 256, 248–255 (2005).
[Crossref]

Zhou, G.

Appl. Opt. (1)

Electron. Lett. (3)

T. R. Clark, T. F. Carruthers, P. J. Matthews, and I. N. Duling, “Phase noise measurements of ultrastable 10 GHz harmonically modelocked fibre laser,” Electron. Lett. 35, 720–721 (1999).
[Crossref]

A. Yariv and R. G. M. P. Koumans, “Time interleaved optical sampling for ultra-high speed A/D conversion,” Electron. Lett. 34, 2012–2013 (1998).
[Crossref]

K. G. Wilcox, H. D. Foreman, J. S. Roberts, and A. C. Tropper, “Timing jitter of 897 MHz optical pulse train from actively stabilised passively modelocked surface-emitting semiconductor laser,” Electron. Lett. 42, 159–160 (2006).
[Crossref]

IEEE J. Quantum. Elect. (1)

M. E. Grein, H. A. Haus, Y. Chen, and E. P. Ippen, “Quantum-limited timing jitter in actively modelocked lasers,” IEEE J. Quantum. Elect. 40, 1458–1470 (2004).
[Crossref]

IEEE J. Sel. Areas Commun. (1)

R. H. Walden, “Analog-to-digital converter survey and analysis,” IEEE J. Sel. Areas Commun. 17, 539–550 (1999).
[Crossref]

IEEE Photon. Technol. Lett. (1)

H. Byun, A. Hanjani, S. Frolov, E. P. Ippen, D. Pudo, J. Shmulovich, and F. X. Kartner, “Integrated Low-Jitter 400-MHz Femtosecond Waveguide Laser,” IEEE Photon. Technol. Lett. 21, 763–765 (2009).
[Crossref]

IEEE Trans. Microw. Theory Techn. (1)

P. L. Liu, K. J. Williams, M. Y. Frankel, and R. D. Esman, “Saturation characteristics of fast photodetectors,” IEEE Trans. Microw. Theory Techn. 47, 1297–1303 (1999).
[Crossref]

J. Lightwave Technol. (4)

Nature Photon. (1)

A. J. Benedick, J. G. Fujimoto, and F. X. Kärtner, “Ultrashort laser pulses: optical flywheels with attosecond jitter,” Nature Photon. 6, 97–100 (2012).
[Crossref]

Opt. Commun. (2)

A. Zeitouny, Z. Tamir, A. Feldster, and M. Horowitz, “Optical sampling of narrowband microwave signals using pulses generated by electroabsorption modulators,” Opt. Commun. 256, 248–255 (2005).
[Crossref]

J. Liu, G. S. Kanter, S. X. Wang, and P. Kumar, “10 GHz ultra-stable short optical pulse generation via phase-modulation enhanced dual-loop optoelectronic oscillator,” Opt. Commun. 285, 1035–1038 (2012).
[Crossref]

Opt. Express (5)

Opt. Lett. (1)

Other (1)

E. Rubiola, Phase Noise and Frequency Stability in Oscillators (Cambridge University Press, New York, 2009), Chap. 1.

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Figures (7)

Fig. 1
Fig. 1 Schematic description of the experimental setup. The RF comb generator is outlined with a dashed red line. LD is a semiconductor continuous wave laser, MZM1 is a MZM used to generate the RF comb, MZM2 is MZM used for under-sampling, PD is a photo-detector, G3 is an RF amplifier with a bandwidth of 0.1 – 3 GHz and a gain of about 30 dB, G1 and G2 are RF amplifiers having a bandwidth of 5.9 – 18 GHz, gain of 35 dB, and a noise figure of 5.5 dB. A1 and A2 are variable RF attenuators, PS is a RF phase shifter, DRO1 and DRO2 are a phase-locked DROs generating 8 GHz and 12 GHz signals, respectively. A 100 MHz crystal oscillator is used to phase lock the two DROs.
Fig. 2
Fig. 2 (a) Measured spectrum of the RF comb and (b) noise floor of the RF spectrum analyzer measured without an input signal. The maximum change of the comb line amplitudes between 4 to 48 GHz is only about 4.4 dB. The RF spectrum analyzer resolution bandwidth (RBW) was set to 100 kHz.
Fig. 3
Fig. 3 Optical spectrum of the frequency comb measured by using an optical spectrum analyzer with a frequency resolution of about 2 GHz. The optical signal was measured via a 1% optical coupler that was connected to the output of MZM2.
Fig. 4
Fig. 4 (a) Waveform of a single period and (b) of 4 periods of the comb signal measured by using a sampling oscilloscope. The repetition period equals T = 250 ps.
Fig. 5
Fig. 5 Phase noise of the RF comb measured by using a signal source analyzer (FSUP26). The measured RMS jitter around (a) 20 and (b) 16 GHz was 11 and 15 fs, respectfully for an integration bandwidth of 10 kHz to 10 MHz. For the comparison, the phase noise of the two DROs that were used to generate the comb are also shown in the figure. The figure shows that the phase noise of the RF comb is dominated by the phase noise of the DROs.
Fig. 6
Fig. 6 Down-conversion of two chirped RF signals centered around 6.9 and 9.6 GHz with a bandwidth of 120 and 200 MHz, respectively. Figure 6(a) shows the input signals spectrum measured by an RF spectrum analyzer and Fig. 6(b) shows the down-converted signals at baseband. Figures 6(c) and 6(d) give a zoom on the spectrum of the RF signal with a carrier frequency of 6.9 GHz and on its down-converted baseband signal, respectively. The down-conversion loss was measured to be about −7.8 dB. The RF spectrum analyzer RBW was set to 150 kHz.
Fig. 7
Fig. 7 Normalized response of the system as a function of the input signal frequency, defined as the signal amplitude at baseband that is measured at the output of amplifier G3, divided by the input signal amplitude. The result was normalized to a down-conversion loss of −7.8 dB.

Equations (2)

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V P D ( f ) = f r n = C ( n f r ) S ( f n f r )
V m ( t ) = m 0 + m 2 sin [ 2 π ( 2 f r ) t ] + m 3 sin [ 2 π ( 3 f r ) t + π Δ ϕ 23 ]

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